640层动态容积CT心电门控技术评估急性胰腺炎脾动脉血管壁弹性变化

Evaluation of Splenic Artery Wall Elasticity in Acute Pancreatitis with 640-Slice Dynamic Volume CT Electrocardiogram Gating Technology

目的应用640层动态容积CT(DVCT)心电门控技术获得急性胰腺炎(AP)脾动脉血管壁弹性度(D)的变化规律,探讨其与改良CT严重度指数(MCTSI)、床旁严重指数(BISAP)的相关性。资料与方法采用640层DVCT前瞻性心电门控技术对40例AP组和21例非AP组受试者进行胰腺增强扫描,获得1个心动周期内脾动脉轴位面积的最大值及最小值,并计算D值。采用受试者工作特征(ROC)曲线评价D值对AP的诊断效能。由MCTSI、BISAP两项指数对AP组的严重程度进行评分,分析其与AP组D值的相关性。结果AP组与非AP组D值分别为(6.09±1.83)×10^-3/mmHg、(8.32±1.05)×10^-3/mmHg,差异有统计学意义(P<0.01)。根据MCTSI评分分级,AP组不同严重程度亚组间D值比较,差异有统计学意义(P<0.05),且中、重度与非AP组D值差异有统计学异意义(P均<0.05)。D值对诊断AP的ROC曲线下面积为0.865,最佳临界值为7.31×10^-3/mmHg,敏感度及特异度分别为80.0%和85.7%。AP组的两项指数与D值均呈负相关(r=-0.937、-0.658,P均<0.001)。结论640层DVCT前瞻性心电门控扫描技术对D值的定量分析可能是对AP的一种影像量化标记,D值的变化表明了AP的严重程度。

Purpose To obtain the changes of splenic artery wall elasticity(D)in acute pancreatitis(AP)using 640-slice dynamic volume CT(DVCT)electrocardiogram gating technology,and to explore the correlations with the modified CT severity index(MCTSI)and bedside index for severity in acute pancreatitis(BISAP).Materials and Methods Pancreatic enhancement scans were performed on 40 patients with AP and 21 cases of non-AP using 640-slice DVCT prospective ECG gating technology.The maximum and minimum values of the splenic artery axial area were obtained in one cardiac cycle,and the D value was calculated.The ROC curve was used to evaluate the diagnostic efficacy of the D value for the AP.The severity of the AP group was scored by MCTSI and BISAP indexes,the correlation between the D value at the AP and the two indexes was analyzed.Results The D values of AP group and non-AP group were(6.09±1.83)×10^-3/mmHg and(8.32±1.05)×10^-3/mmHg,respectively,with statistical difference(P<0.01).According to the MCTSI scoring,there was a significant difference in the D value between the subgroups(P<0.05);and there was a significant difference in the D value between the non-AP group and the moderate as well as severe levels(all P<0.05).The area under curve of D value for diagnosing AP was 0.865,with the optimal cutoff 7.31×10^-3/mmHg,the sensitivity and specificity were 80.0%and 85.7%,respectively.Both indexes of the AP group were negatively correlated with D values(r=-0.937,-0.658,P<0.001).Conclusion The quantitative analysis of D value by 640-slice DVCT prospective ECG gating technology may be a quantitative marker of AP.The change in E indicates the severity of AP.